Electrically heated hair roller with self-contained power source

ABSTRACT

A hollow tubular hair roller about which hair may be wound incorporates a resistive heating element in its tubular wall structure. A battery, which may be rechargeable, is supported within the hollow interior of the roller and connected to the heating element. A zone of heat insulation at least one-sixteenth inch deep and having a thermal conductivity less than 0.003 cal./(sec.) (cm.2) (* C./cm.) is provided between the resistive heating element and the battery. The zone of insulation may be a tube of solid or foamed synthetic polymer or an airgap through which battery supporting nibs extend.

United States Patent [72] Inventor Donald Ulldmwd 2,394,973 2/1946Bergen 219/222 UX Northbrook, 111. 2,727,132 12/1955 Hills 219/240 UX[21] Appl. No. 868, 09 3,141,956 7/1964 Schoenwald 219/240 UX [221 Fil d1969 3,196,883 7/1965 Zentko 219/222 x 1 1 Patenwd p 7,1971 3,419,70412/1968 Hunt 219 240 x 1 1 Assignee The Gillette p y 3,486,000 12/1969DElia e161. 219 222 Boston, Mass- 3,518,7ll 7/1970 Radclifie 320/2 XPrimary Examiner-A. Bartis [54] ELECTRICALLY HEATED HAIR ROLLER WITH yFurlong SELF-CONTAINED POWER SOURCE 8 Claims, 6 Drawing Figs.

{52] US. Cl....; 219/222, ABSTRACT: A hollow tubular hailroner aboutwhich hair 132/33 R, 219/240, 219/242, 219/531, 2 /2 ay be woundincorporates a resistive heating element in its [51 Int. Cl A451! 2/36,tubular wall structure A battery hi may be rechargeable,

3/00, 45/04 is supported within the hollow interior of the roller andcon- Field Of Search ..2l9/222226, named to the heating element A zone fheat insulation at 221, 227-242, 531 132/33 R, 36 l ast one-sixteenthinch deep and having a thermal conductivi- 320/2 ty less than 0.003cal./(sec.) (cm?) C./cm.) is provided between the resistive heatingelement and the battery. The [56] References Cited zone of insulationmay be a tube of solid or foamed synthetic UNITED STATES PATENTS polymeror an airgap through which battery supporting nibs 1,666,269 4/1928Smidt 132/33 R extend.

I l I ELECTRICALLY HEATED HAIR ROLLER WITH SELF- CONTAINED POWER SOURCEThis invention relates to portable heating hair rollers. Heat is usefuladjunct in many cosmetic treatments as well i asin the setting of hair.It is known that the bleaching, waving and dyeing processes are allusefully accelerated by heat. It is 1 also known that the effects ofconditioning treatments consisting of lanolated oils, olive oil, orfatty cationic compositions .are enhanced by heat. Heat is also usefulin the straightening of hair.

A variety of devices for the heating and setting of hair have been used,including hot-air blowers, preheated rods or rollers, and curlerscontaining chemical agents or embedded electrical heating elementsenergized by outside sources such as household current available athousehold outlets.

Hot-air blowers are usually bulky to store and inconvenient to use. Incommercial establishments they are of the type that allow the subject tomove her head slightly within the device but require a fixed bodyposition. Home hot-air blowers generally include a cap which is fixed onthe subject's head, allowing her to move-more-freely but even thismobility is 1 limited by connections .to the blower supplying hot air tothe cap. The cap, moreover, is often insecurely and uncom- 3 fortablyfixed on the subjects head.

Individually heated hair rollers have solved some of these -.problems,but caused others. Hair rollershave been devised to be heated before useand then applied to'the head to have the 1 heat transferred to the hair.Since the rollers cool on the head an initially large heat reservoir isrequired. Besides, the high temperatures needed are supplied bypreheating devices which. are often dangerous to use and control, andhandling plied with'electricity from household outlets, usually througha stepdown transformer so that the voltage of elements on the head isata safe minimum. Mobility of the user is limited by theelectricalconnection required. At low voltages, large cur-. .rentsandcurrent-carrying equipment are needed to supply adequate heating energy.Wires leading to all the curlers are inconvenient and a safe way ofdisconnecting unneeded curlers must be devised.

The object of the invention, therefore, is to provide invdividualheatinghair curlers that are comfortable and convenient to use, that are simpleand safe to activate and use in the hair, that allow mobility of theuser, that may be used in .any number desired, and that are easily andinexpensively manufactured.

The invention features a hair roller made of a structure having anelectrically insulated resisting heating element about which hair may bewound, the structure supporting a battery to be connected to theterminals of the resistive element. In preferred embodiments the batteryis disposed within the structure andthe structure has a low heatcapacity and a zone of heat-insulation at least one sixteenth inch deepbetween the resistive heating elementand the battery, the zone having athermal conductivity less than 0.003 cal./(sec.)(cm. )(C./cm.). In somecases the zone of insulation is a tube of solid or foamed syntheticorganic polymer, in others an air gap through which battery supportingnibs extend.

Other objects, features, and advantages will appear from the followingdescription of preferred embodiments of the invention, taken togetherwith the attached drawings thereof, in which:

FIG. 1 is a longitudinal sectional view of a first hair roller embodyingthe invention;

FIG. 2 is a perspective view of a battery-charging unit for the rollers;

FIG. 3 is a longitudinal sectional view of a roller of FIG. I insertedin the battery-charged unit;

FIG. 4 is a perspective view of a dummy plug for deactivating the hairroller;

FIG. 5 is a longitudinal sectional view of a roller with the dummy pluginserted; and

FIG. 6 is a cross-sectional view of a second roller embodying theinvention.

FIG. 1 shows a hair roller 10, a conductive battery plug I2, and abattery 14 inserted into the hairroller.

The hair roller includes a tube I8 made of Teflon(polytetrafluoroethylene), a fluorocarbon polymer. The tube has athermal conductivity of about 0.0025 cal./(sec.)(.cm. )(C./cm.). Thetube is about one-sixteenth ofan inch'thick.

A resistive heating element 20 surrounds the outside of tube 18in theform of a steel tape helically wound about thetube so that it issupported by'and secured to the tube. Heating element 20 is covered withan-epoxy varnish 22, which together with tube 18 provides electricalinsulation for element 20.

The heating element on one end is electrically connected to a batterycontact 26. Contact 26 is supported by tube'l'8so that the contact alsoacts as a support forbattery 14. The heating elements other. end isconnected to a conductive ring 28,

secured to the roller. Battery plug l2isthreadedlyconnected to theconductive ring.

The roller may be of any desirable shape other than the cylindricalshape shown. Cylindrical forms of the roller may vary in outsidedimensions from one-fourth'to 2% inches in diameter and one-half inch to12 inches in length. Long curlers may be flexible for uses such assetting a page boy hair style and may require more than one battery.

The tube 18 must absorb little of the heat given off by the heatingelement. This is accomplished by using a composite material of lowspecific heat, and as little of that material as possible, thusaccomplishing the'additional'beneficial-result'of lightening the .hairroller so that it may be worn comfortably. The material of which thetube is made must also providcsufficient strength to stand the stress ofrolled hair, bothat room temperature and at operating temperatures of atleast 50 C.

In order to supply adequate heat for setting of hair and for variousother cosmetic purposes the power supply, represented by a battery inthis case, should yield one'eighth to 3 watts per square inch of surfacearea of the roller with a preferred range being one-fourth to 2 wattsper square inch. For example, batteries whose voltage is about 1.2 voltsand whose ampere hour capacity is in the range of at least0.5 to 1.0ampere hour and are designed for fast discharge rates, such as CH500(Eveready), CH750 (Eveready), G.C. 5 (General Electric), G.C. 6 (GeneralElectric), or G.C. 10 (General Electric), may beused effectively.

Even minimum energy cells, such as carbon-zinc batteries, can functionin embodiments of the invention; alkaline batteries are obviouslyuseful. For quick settingof dry hair theattainment of a temperature ofat least 50 C. at the'outer surface of the roller for at least 10minutes is desirable. A battery and roller construction that yields atemperature of even 35 C. is useful for other applications such asbleaching, waving, dyeing or the like. When cells are used that arecapable of discharging in still less time, the temperature reached ishigher and the totalenergy required is much less. This is because theefficiency of setting of dry hair is roughly proportional to thetemperature rise above 50 C.

Other resistive heating elements beside steel tape are useful, e.g.Nichrome wire, plastic-clad aluminum, carbon-filled fiber fabrics. Themethod of applying wire or tape to the tube surface need not berestricted to a spiral wind since awaffle pattern, or a longitudinalwind, is equally effective. Printed-circuit resistive elements may alsobeutilized.

In order to avoid excessive loss of the heat generatedbythe resistiveelement to the battery itself which isa considerable component of themass of the roller when used, it is essential that the battery bethermally insulated from the heating element. A thermal insulation zonebetween the battery and heating element at least one-sixteenth inchthick is required, in which the thermal conductivity is no greater than0.003cal./(sec.)(em. )(C./cm.). cal./(sec.)(cm.

In the roller shown in FIG. I the required zone of thermal insulation isprovided by tube 18. Many other materials may be used for the tube, suchas nylon, polycarbonates, phenolics, glass filled polycarbonates,polyphenyloxides, paper and cardboard.

Battery 14 of the embodiment shown in FIG. 1 is rechargeable. Abattery-recharging unit, generally designated 30, is shown in FIG. 2.Unit 30 includes a base 32, a cover 34 and a cord 36 supplying electricpower to a conventional charging circuit (not shown). Battery-rechargingelements such as plugs 40 connected to the circuit are found in base 32of the unit within recesses 42 large enough to accommodate hair rollers10.

Each recharging element such as plug 40 (FIG. 3) has an inner firstconductor 50 and an outer second conductor 52 separated by an insulator54. Inner first conductor 50 of the plug has a ball-like top 56 mountedon a core 58 which extends to a base 60. Insulator 54 includes a sheath62 surrounding core 58 which terminates in a base 64 atop firstconductor base 60. Outer second conductor 52 includes an annular portion66, spaced below first conductor top 56, surrounding insulator sheath62. Annular portion 66 terminates in a base 68 atop insulator base 64.

The bases 60 and 68 of the first and second conductors 50 and 54,respectively, have extensions 72 to which are connected leads 74 to acharging circuit. Battery-charging circuits are well known to thoseskilled in the art and such a circuit is not shown for purposes ofclarity. A diode 78 is inserted in one of the leads to each plug 40 toprevent discharge into the charging circuit by a fully charged batterywhen batteries of varying states of charge are present in the unit.

The end of hair curler adjacent contact 26 has an opening 80 which iscircular in cross section, with an inside diameter slightly larger thanthe outside diameter of recharging plug 40. A lead 82 extending toconductive ring 28 but insulated from resistive heating elementterminates in a bowed metallic contact 84 on the interior wall ofopening 80.

Contact 26 includes a support section 90 embedded in the roller. Onepart of support section 90 extends inwardly to become a batterysupporting and contact arm 92. Another part of the support section(electrically connected to the first) extends in the form of a leafspring contact 94 to a point contact 95 for connection with a lead 96connected to resistive heating element 20. Leaf spring contact 94 forms,in one portion, an arcuate protrusion 98 extending into a cavity 100between battery 14 and opening 80. Leaf spring contact 94 is biased sothat pressure upon protrusion 98 breaks the electrical connectionbetween point contact 95 and lead 96.

A dummy plug 102 (FIG. 4), made of electrically nonconductive material,has the same upper configuration as recharging plug 40.

During use, hair is wrapped around hair roller 10 in the ordinaryfashion. Resistive heating element 20, connected at one end to 'oneterminal of battery 14 via battery plug 12 and conductive ring 28, andat the other end to the other terminal via lead 96 and contact 26, isheated by the passage of electric current through it (FIG. 1). Battery14 is supported within the roller by battery plug 12 and arm 92 ofcontact 26. The battery may be removed by unscrewing battery plug 12.

The batteries in the rollers may be recharged by usingbattery-recharging unit 30. Hair rollers 10, bearing batteries 14, areplaced, opening 80 downward, into recesses 42 in the unit base (FIGS, 2and 3).

Recharging plug 40 enters cavity 100 in the roller through opening 80(FIG. 3). Ball top 56 of the first inner conductor 50 presses againstprotrusion 98 of contact 26, breaking electrical contactbetween battery14 and lead 96 by moving point contact 95 away from lead 96. Ball top 56also comes into firm electrical contact with protrusion 98 and thereforewith one terminal of battery 14 through portions 94, and 92 of contact26. Annular portion 66 of outer second conductor 52, in opening 80, ispressed against by bowed metallic contact 84 and is therefore inelectrical contact with the other terminal of battery 14 via lead 82,conductive ring 28 and battery plug 12. Electric current from thecharging circuit, supplied to recharging plug 50 by leads 74 via plugextensions 72, is thus transmitted to battery 14 to recharge it.

When a roller 10 is removed from battery charging unit 30 point contactreturns to electrical contact with lead 96 and energization of resistiveheating element 20 resumes. If delay in the energization of the heatingelement is desired dummy plug 102 may be inserted (FIG. 5). Having thesame configuration as recharging element such as plug 50, the dummy plugwill also cause point contact 95 to move away from lead 96, breaking thecircuit of resistive heating element 20 and stopping heating. When thedummy plug is removed, heating resumes.

An alternate embodiment of the invention is shown in FIG. 6. Shown are abattery 214 electrically connected to an epoxy varnish covered resistiveelement 220 formed, as in the first embodiment, by a spirally woundsteel tape mounted on tube 218. In the alternate embodiment, however,battery 214 is not laterally supported by the inner surface of tube 218but rather by electrically insulating support elements such as nibs 224extending inwardly from the inner surface of tube 218, the thickness ofthe tube in the alternate embodiment being only one-fiftieth inch, andthe length of the nibs one-sixteenth inch.

In the alternate embodiment the use of nibs 224 reduces the amount ofmaterial in the tube of the hair roller and reduces its weight. It alsomakes possible the use of materials for construction of tube 218 ofrelatively high conductivity such as aluminum (properly electricallyinsulated) The one-sixteenth inch airgap between tube 218 and battery214 serves as an effective component of the zone of thermal insulationrequired, since the thermal conductivity of air is about 0.0005 cal./(sec.)(cm. For additional structural strength of the tube, however, theairgap may be filled between adjacent nibs with such air-containing,heat-insulating materials as glass wool, foam plastic or vermiculite. Inthe embodiments of FIG. 1 and FIG. 6 the spiral conductor may bereplaced by a tube or cylinder of wire mesh, the cylinder being of largeenough diameter to fit over tube 18 or 218. The latter may be perforatedto reduce weight and heat capacity. If desired, the perforations may beof such size and shape as to match the interstices of the wire mesh, towhich it is secured.

It will be appreciated that the individual rollers, including theirbatteries, are normally kept in recharging unit 30 which serves both forrecharging and for storage. Whether the unit is connected to a powersupply or not the batteries are disconnected from heating elements 20,220 so long as the rollers are mounted on plugs 40, and no appreciabledischarge of the batteries or heating of the rollers occurs during suchstorage. Accordingly, when removed from unit 30, the rollers are cold tothe touch, but become warm during the process of wrapping hair uponthem. If for any reason it is desired to have the rollers remain outsideof charging unit 30 for a substantial period of time without heating, adummy plug 102 is inserted in each roller to interrupt the circuit bybreaking the contact between point 95 and lead 96.

Even if the rollers are removed from charging unit 30 and allowed toheat up before the hair is wrapped upon them, the low heat capacity ofeach roller makes it possible for the rollers to be handled and usedwithout gloves and without risk of burning the hands or fingers,differing in this important respect from conventional curlers which arepreheated before use and which depend upon the high heat capacity of thecurler for their effectiveness.

Other embodiments will occur to those skilled in the art and are withinthe following claims.

What is claimed is:

1. A hair roller comprising a hollow tube about which hair may be wound,

an electrically insulated resistive heating element extending about thewall of at least a portion of said tube,

said tube including means for supporting a battery in a location withinthe hollow interior thereof with at least a portion of the batterypositioned in said portion of the tube provided with said heatingelement and including a heat insulating zone substantially coextensivewith said portion of the battery and at least one sixteenth inch thick,said zone having a thermal conductivity no greater than 0.003cal./(sec.)(cm.)(C./cm.) and being disposed between said heating elementand said battery location,

and meansfor electrically connecting said heating elemen to a battery sosupported.

2. A hair roller as claimed in claim 1 in which said heating element isdisposed in helical form about said tube and extends the full length ofsaid battery location.

3. A hair roller as claimed in claim 1 in which said supporting means isarranged to maintain said battery in spaced relation to the wall of thetube, said space between the battery and the wall forming at least aportion of said heat insulating zone.

4. A hair roller as claimed in claim 1 in which the wall of said tubecomprises a thickness inwardly of said heating element of at least onesixteenth inch, composed of material having a thermal conductivity lessthan 0.003 cal./(sec.)(cm. )(C./cm.) forming said heat insulating zone.

5. A hair roller as claimed in claim 3 in which said heating elementextends the full length of said battery location.

6. A hair roller as claimed in claim 5 in which said heating elementextends the full length of said battery location.

7. A hair roller as claimed in claim 1 in which said battery isrechargeable, said electrical connecting means is normally closed and isactuatable to open position, and said roller includes an element forconnecting said battery to a source of recharging power and forsimultaneously actuating said electrical connecting means to openposition to disconnect said heating element from said battery.

8. A hair roller as claimed in claim 7 including an additionalelectrically nonconductive element interchangeable with said connectingelement for actuating said electrical connecting means to open positionto disconnect said heating element from said battery without connectingsaid battery to a source of recharging power.

UNLTED STATES PATENT OFFICE PO-TOSO CERTIFICATE OF CORRECTION Patent No.3 603 765 Da d September 7, 1971 Inventor s Donald L. Underwood It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 1, line 5?, "resisting" should be --res1stive--;

Column 3, line delete after "(C/cm)." the words "cal/(sec)(cm.";

Column 3, line 12, after "dummy", insert --element such Column 4, line14, after "recharging", delete --element such as--;

Column 4, line 38, insert after "(cm --(C/cm).--.

igned and sealed this 28th day of March 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR.

Commissioner of Patents

1. A hair roller comprising a hollow tube about which hair may be wound,an electrically insulated resistive heating element extending about thewall of at least a portion of said tube, said tube including means forsupporting a battery in a location within the hollow interior thereofwith at least a portion of the battery positioned in said portion of thetube provided with said heating element and including a heat insulatingzone substantially coextensive with said portion of the battery and atleast one sixteenth inch thick, said zone having a thermal conductivityno greater than 0.003 cal./(sec.)(cm.2)(*C./cm.) and being disposedbetween said heating element and said battery location, and means forelectrically connecting said heating element to a battery so supported.2. A hair roller as claimed in claim 1 in which said heating element isdisposed in helical form about said tube and extends the full length ofsaid battery location.
 3. A hair roller as claimed in claim 1 in whichsaid supporting means is arranged to maintain said battery in spacedrelation to the wall of the tube, said space between the battery and thewall forming at least a portion of said heat insulating zone.
 4. A hairroller as claimed in claim 1 in which the wall of said tube comprises athickness inwardly of said heating element of at least one sixteenthinch, composed of material having a thermal conductivity less than 0.003cal./(sec.)(cm.2)(*C./cm.) forming said heat insulating zone.
 5. A hairroller as claimed in claim 3 in which said heating element extends thefull length of said battery location.
 6. A hair roller as claimed inclaim 5 in which said heating element extends the full length of saidbattery location.
 7. A hair roller as claimed in claim 1 in whiCh saidbattery is rechargeable, said electrical connecting means is normallyclosed and is actuatable to open position, and said roller includes anelement for connecting said battery to a source of recharging power andfor simultaneously actuating said electrical connecting means to openposition to disconnect said heating element from said battery.
 8. A hairroller as claimed in claim 7 including an additional electricallynonconductive element interchangeable with said connecting element foractuating said electrical connecting means to open position todisconnect said heating element from said battery without connectingsaid battery to a source of recharging power.